Your Home Doesn't Matter for Tesla's Dream of a Battery-Powered Planet
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927 kwh / month off grid solar system : http://www.wholesalesolar.com/solarpowersystems/large-home-7...
Cost : $20,172
Two of Elon's batteries: $7k
Total cost = $27,172
How the hell did they get $98k?
I think they intentionally tried to make that number look ridiculous. I wonder if this is more of ALEC's anti-solar bullshit.
[0] http://energy.gov/savings/residential-renewable-energy-tax-c...
Furthermore, the 10kWh Powerwall is not for solar or other daily applications; it's for backup.[1] A PV system needs to use the 7kWh batteries, thus requiring 9 for this system. That is $27,000 in batteries.
Now, on to the panels. The sizing of the system you posted indicates it assumes 5 Sun hours per day. Most of the US gets less than that; from the map on the site it looks like 4.3 is a good average for the US. Next, as the site clearly says when you run their off-grid calculator, you need to discount the Sun hours if you plan on using the system in the winter; they recommend knocking 1.5 off your yearly average. That drops most of the US to 2.8. That means the median house would need twice the number of solar panels in that set to cover all times of year.
Combined with the actual cost of Powerwall batteries, we are at $67,344. If you want to use the Pacific Northwest as your baseline (which someone opposed to solar would try to do) you approach the $98,000 for an off-grid system.
Oh look. It's $8k. So the total price is $28k.
62 kwh is over two full day's worth of electricity usage for the average US home. I actually think that's probably quite a bit more than you need. Two of Elon's batteries is 20kwh, which is about 2/3 of an average day's usage - enough to last most people the night, right?
>Now, on to the panels. The sizing of the system you posted indicates it assumes 5 Sun hours per day. Most of the US gets less than that
$98k was in California right? According to this, Los Angeles gets 5.62. Manhattan gets 4.57.
http://www.bigfrogmountain.com/SunHoursPerDay.html
>it looks like 4.3 is a good average for the US
Why not pick 3.9 and assume that everybody gets as much as Fairbanks, Alaska?
Yes, and the sentence you quoted specifically said the $98,000 figure was using Tesla's batteries.
> 62 kwh is over two full day's worth of electricity usage for the average US home. I actually think that's probably quite a bit more than you need. Two of Elon's batteries is 20kwh, which is about 2/3 of an average day's usage - enough to last most people the night, right?
Wrong. An off-grid PV system requires a buffer to supply power during days with little to no sun. Two days is about right for most of the country; in some places I would size it larger because they are prone to multiple days of overcast conditions at certain times of year.
Furthermore, you completely ignored that I stated, supported by the link I provided to the Tesla page, that you are not supposed to use the 10kWh batteries for daily drain applications.
> $98k was in California right? According to this, Los Angeles gets 5.62. Manhattan gets 4.57.
I didn't look into where the $98,000 was supposed to be located. I assumed they took the least-favorable location in the country.
> Why not pick 3.9 and assume that everybody gets as much as Fairbanks, Alaska?
Because the vast majority of the US gets in the range of 4.2 - 4.5? I could have used 4.5, but that would only move the total cost down by about $4,000. Still, that is the average. An off-grid system needs to be designed for the low on that chart, or there will be times of year you have little or no power.
Ok, so assuming that you really do need ~60kwh and you must use Tesla's expensive batteries rather than the $8k package, that's still 21 + 3 * 8 batteries = $45k for a house in California. What is the other $53k spent on? Postage?
>I didn't look into where the $98,000 was supposed to be located. I assumed they took the least-favorable location in the country.
In California. It's right there in my first post.
Maybe they assumed that the average American lives in Alaska and use their air conditioning 24/7.
“The battery-in-every-home idea—not only do I think it doesn’t make economic sense, I don’t think it’s necessary,” said Brian Warshay, an analyst at Bloomberg New Energy Finance. “Having a centralized grid is incredibly useful and incredibly efficient.”
The difficulty with our current power infrastructure is that there is no buffering at the consumption side. Because there is no buffering at the consumption side, the overall grid must be able to handle peak demand. That is, we must over-provision. With batteries everywhere, this isn't necessarily the case. In theory, we could all have generators, but we don't because they're noisy, smelly, and a maintenance hassle. But sticking a giant battery on the wall? I can see everyone having one, and big institutions having large arrays of them. I think that has the potential to fundamentally change our power grid.
https://en.wikipedia.org/wiki/Bath_County_Pumped_Storage_Sta...
Do you have any idea how many Li-Ion batteries would be needed to match the 30 GIGAWATT-hours of storage potential in the Bath County pumped storage plant?
The problem is that California didn't build enough of these 20 years ago. California has a couple of pumped-storage plants coming in... and as soon as they're built then net-metering will be even better for consumers.
In general, centralized storage at the utility-level will benefit from scale. Redox batteries will probably be cheaper and more efficient than Li-Ion batteries that Tesla is putting out.
And Pumped-Hydro is already much much cheaper, and has existed since the 60s.
like the ability to store up power from home solar
or the ability to keep your furnace running in a power outage.
In any case, a "total" solution for a 10kw gas backup power can be had for less than $7,000, including installation costs. While the 10kw battery solution is closer to $15,000+.
A Gas Generator can be wired up to either a propane tank, offering perpetual energy. (Gas lines rarely rupture). If you don't want to be hooked up to gas lines, then propane tanks are also an option.
That's great in places where the grid is required to take your excess power at rates similar to what you will end up paying at the times you may want to buy it back.
How many places does that apply to? (EDIT: I'm genuinely curious; it's not a rhetorical question, just to be clear)
On the contrary. Any form of net-metering makes batteries a hopeless situation.
Lets say you use net-metering, and it returns power at less than HALF of "off peak" levels. Lets say you're paying absurd California prices, of 40-cents kw-h at peek, and 10-cents at non-peek. And then you only manage to sell power back at 4-cents.
IIRC, these numbers are somewhat close to California numbers. Mind you, Virginia has 9-cents peek and 1-cent off peek. So... California prices are about as good as it gets for batteries.
Well, lets see here... first off all, you don't pay peek anymore. Because your solar panels are active between 11am and 4pm. Lets say you're selling it back at 4-cents. So you're paying in essence... 6-cents for nighttime power through the net-metering system (for every kw-h stored in excess by your solar panels)
You need to use 58333 kw-h before you break even with Tesla's $3500 battery (not counting inverter costs or installation costs). Considering that the battery has a capacity of 7kw-h, that is 8333 cycles or 22-years.
Unfortunately, the Tesla Battery Pack only has a 10-year lifespan. So you've lost money in the long run.
Not counting inefficiencies in the battery, inefficiencies in the inverter or installation costs.
They kill people on a regular basis (due to misuse, but misuse happens). I don't need 10KW, either, I just need enough to power the furnace so I don't freeze to death.
> Why would you want to do this when net-metering exists? Let the grid store your excess power, and buy it back from them. Run the math, you'll see which one is cheaper.
The math will change if everyone does it, I'd imagine.
> I don't need 10KW, either, I just need enough to power the furnace so I don't freeze to death.
Erm... what kind of furnace is in your house?
http://www.shop.thefurnaceoutlet.com/Electric-Furnaces_c15.h...
Ignoring the fact that furnaces are typically 10kw or more... then lets say you "only" need 3kw of power (so you can run off of a single Tesla battery). (Maybe you're running a smaller room-heater or something)
Then why not get a smaller $500 generator?
http://www.amazon.com/DuroStar-DS4000S-4-Cycle-Portable-Gene...
Or I dunno... a fireplace at that point. Since we're talking about small scale if you're using something smaller than a 10kw furnace...
A natural gas furnace, which needs a small amount of power to start and continue running.
> Then why not get a smaller $500 generator?
As a non-mechanical person, I'd rather not have to maintain one. The lawnmower is enough for me. I also like the idea of being able to have some additional powered items plugged in in an extended outage.
Hmm, at which point I wonder if your standard UPS actually does the job. When I think "PowerWall", I'm thinking of things that power the entire house.
But UPSes are useful for the small-scale "important" appliances. Like the sump pump or I guess in this case... a gas furnace.
APC UPSes are only about $500. My parents had flooding issues with their Sump Pump as power went out a few years ago, and they just installed some UPS on it. Haven't had a problem since then.
http://www.tripplite.com/shared/literature/white-paper/how-t...
I'll have to go to their basement to figure out which brand they bought. But the above whitepaper gives you an idea of how it works with a sump pump.
Sounds a hell-of-a-lot cheaper than the Tesla Powerwall still.
EDIT: Seems like some guy in the UK has done the calcs already. http://kissurvival.com/running-your-gas-furnace-from-a-gener...
Tesla's Superfactory could produce that. In about 12,000 years.
Even if the capacity's excessive by a few orders of magnitude, that's a hell of a lot of battery.
http://physics.ucsd.edu/do-the-math/2011/08/nation-sized-bat...
Assuming 56 kWh Tesla batteries. Half a million battery packs is 28 GWh of total storage capacity. That's the energy equivalent of 16,000 barrels of oil. Assuming a modest 30% Carnot thermal generation efficiency, you'd need 55,000 bbl of oil to actually generate that electricity.
Yeah, batteries are a hard sell.
If each battery is 2m x 3m or 6m in area, the Nation Sized Tesla Battery would cover 36,000 km^2, or an area 190 km on a side. Maybe we'll stack them.
(The actual measurements are smaller, around 1.5 x 2.5 m or so, so that's an overstatement.)
A buddy of mine working at ORNL claims there's interesting stuff on the storage front that's competitive with pumped storage, but can't say just what yet. I'm highly curious myself.
http://prod.sandia.gov/techlib/access-control.cgi/2011/11273...
"Table 4" is probably what you want to look at. As you can see, only Compressed Air is competitive with Pumped Hydro as far as energy storage (w-hrs).
It looks like Compressed Air is going to be the golden standard a few years from now. There was a relatively cheap compressed-air plant created out of abandoned mine tunnels that was hundreds-of-Megawatts in scale. I don't quite remember the name of it however.
Also, Compressed Air doesn't require you to empty a lake (and refill it) every day. So California's low-water situation may prefer compressed air storage systems.
Redox Flow batteries look to be the most promising technology at utility-scale chemical. Chemical solutions are needed for their versatility... but "long-term" energy storage (such as day-night load balancing) will likely be handled by Compressed Air and/or Pumped Hydro.
Currently, over 95% of the US's energy storage capacity is in pumped hydro.
For example: http://sigmaenergystorage.com/?page_id=447&lang=en
Advances are being made at _all_ energy storage solutions. Frankly, CAES is the most promising, now that they've figured out how to store excess heat during compression.
Thanks for that, could be, and you're likely right, though my understanding was that the work he's discussing hasn't been published. Hard to see it _not_ being CAES though.
Another avenue I've looked at is ocean-based pumped-hydro. Same as the usual suspects, but the ocean is the lower (and hence inexhaustible) basin. That means creating an elevated high-fluctuation saltwater estuary, and you've got corrosion issues associated with salt water, plus marine life fouling. Japan's built a test facility. Tidal barrier systems can also be considered as such (with or without active pumping).
https://www.reddit.com/r/RenewableTech/comments/29t6t7/seawa...
http://www.hitachi.com/rev/1998/revoct98/r4_108.pdf
http://www.inference.phy.cam.ac.uk/sustainable/book/tex/Lago...
http://www.sciencedirect.com/science/article/pii/S1876610214...
Flow, liquid metal, and molten salt batteries also have my eye.
Its not about whether or not someone can produce the batteries. Its about whether or not its cheaper to build centralized storage. Frankly, Pumped Hydro is extremely cheap in contrast to batteries.
Do you want to spend $5 Billion on a pumped hydro station? Or do you want to spend $1,200+ Billion mining a volatile metal out of the ground and building chemical batteries?
I think it is clear which solution is better for America in the long run.
So hopefully less than $3.6 billion in cells (factory direct, new factory aimed at reducing costs). There is a bunch more of stuff in the integrated units, at the quoted $3000 price, 4.3 million of them would be ~$14 billion.
I think pumped storage is great (I've posted enthusiastically about it here in the past), but the sneaky factor is that they did a good job siting the ones they built decades ago, many of the great spots to build them are in use already.
(I edited in the $14 billion after I realized I was talking about a product with a proposed price, I had originally said something about less than $10 billion)
Technically, the Bath County station was built with $1.6 Billion. I adjusted up to $5 Billion for an off-the cuff "inflation" estimation, also because other pumped hydro solutions are coming around $5 Billion as well.
Something to note is that the Bath County station has been running since the 1970s. That's a useful lifespan well of 40 years at this point. I don't think Lithium Ion (especially when they are cycled daily) will achieve that lifespan.
And there are reasons to expect the benefits of new pumped storage to decline over time (the best, most cost effective sites get built first, that sort of construction is well developed technology), and conversely, some reasons to expect the costs of batteries to decline over time (chemistry is still inching forward, as costs come down the number of uses goes up).
Ultimately, I can see that I'm not running out to buy solar panels and house batteries, so my real opinion on what is best right now is clear enough.
Maybe you could store enough energy to run your datacenter overnight. I'm speculating, but powering a chip fab or even a machine shop on batteries seems infeasible.
But, I agree that there is a major imbalance and generation/storage on the consumption side would help correct that. Reduced need for peak generation --> greater net efficiency.
The real market potential for batteries is not in those parts of the West where there is cheap, reliable mains. It's those places where the grid is unreliable enough that people with money would buy generators, or places where the grid is a tiny island (Hawaii, Orkney).
High-rise office and apartment buildings probably don't have space to store all those batteries. If you have a suburban home with a garage you can hang a battery on the garage wall, but if you live in a 20-story apartment building, where would you put it? I doubt that fire codes would allow putting huge lithium batteries inside every apartment. A large fraction of the U.S. population lives in this kind of densely-packed urban environment.
No kidding this isn't (currently) attractive for North American homes. If I recall correctly, they basically said that in the press conference, though I can't find the link now. They were expecting it to be more useful in places with lots of solar and dodgy electric grids, such as Australia.
Bloomberg also goes on and on about utility scale storage. They apparently didn't read the press kit, where Tesla talked about how they're doing just that.
Press Kit - http://www.teslamotors.com/presskit
It IS intentional. Pretty much everything said (and NOT said) on MSM is intentional.
I remember what I thought: How stupid someone could be. It does not make financial sense at all when it was so expensive.
Turn out I was the stupid one. This man created a company doing exactly what he had done in his house but for others and made a ton of money.
In some way he paid a cost for living in the future, and he understood the practical shortcomings and advantages of the new technology much better than anyone else, which made him succeed when others failed.
That being said, electric companies aren't stupid. If / when solar power and batteries become ridiculously cheap, they will just switch over to solar and batteries.
Residential off-the-grid solar power will make sense in two markets: - Highly rural areas where it's very expensive to maintain power lines. - "Be prepared" cultures like Utah where people take pride in preparing themselves for Armageddon.
[1] http://www.greentechmedia.com/articles/read/1.2-Trillion-Met...
Next - If I have a $500K+ house (modest, by Northern California standards), and for $10K I could get this sleek, hi technology, 10 year warranty battery that lets me more efficiently leverage my solar panels, plus potentially giving me some insurance against a grid outage? Hell, I'm first in line.
Now, does the Tesla Battery make sense, for 100% of the US Population, today? Of course not - but I don't think anyone has suggested that.
But this is where we start, and we improve from here.
Net-Metering from those who can afford rooftop panels can then store the energy centrally, and then offset the costs for the non-solar users in the rest of the neighborhood.
Which is true in some countries.
A single 100MW turbine can store weeks-and-weeks of power if drawing from any small lake. But for it to be useful to a lot of people, you probably need to build a gigawatt scale turbine.
With that said, the Bath County generator is the largest in the world, and is close to 30 GW-hr of capacity (3GW of power. Yes, it can empty the lake in 10 hours, and refill it in another 10 hours)
In terms of Storage Capacity of a Dam, I checked: http://www.nps.gov/lake/learn/nature/storage-capacity-of-lak...
The water available for power generation starts at 1050 feet, and goes to 1221.4
The Capacity goes from 11,474,857 acre feet to 31,141,756 acre feet. So Hoover Dam has an operational storage of 19,666,899 foot acres
The Turbines have a capacity of 2,080 MW. From: http://www.usbr.gov/lc/region/pao/brochures/faq.html#capc we discover
What is the maximum capacity of these works?
About 118,000 cubic feet per second: 32,000 cubic feet per second for power generation and 86,000 cubic feet per second of valve discharge. One cubic foot per second of water equals nearly 7 gallons passing a given point in one second.
So, dividing 19666899 foot acres / 118000 cubic feet/second = 6,408,487,134,720 gallons / 882,701.2987 gallons/second = 7,260,085.76644 seconds = 2,016.69049 hours (only 12 weeks)
So, the operational storage capacity of Hoover dam is 2 GW * 2000 Hours = 4 Terawatt Hours. I realize these are entirely different projects, but it's interesting to get a gut sense of how incredibly large the Bath County generators are - not only do they generate power going down - they can also pump that water up.
Incredible - wonder of the world.
Once again a news outlet (deliberately) fails to see the long-term strategy for the sake of a click-baity nay-saying headline. Just like the Tesla vehicle itself, which is still outside the reach of 99% of Americans, the point is to aim for the luxury market first and through scale and process optimization gradually lower the price so that it is within the reach of most Americans.
The luxury market is why Tesla is now able to develop a mass market vehicle, why solar panels are reaching an inflection point where in many parts of the world it will no longer make financial sense not to have them, and why home batteries will eventually be in the reach of everybody.
You can buy batteries for your home, today, at a retail price half that of the Powerwall. With equal or greater energy storage, power output, and lifetime. There's no need to wait for Li-ion to become "within reach". It's a needlessly expensive technology and product attempting to displace cheaper, more capable solutions that have been available for years.
Their marketing sure is clever, though; they're already the only battery system that 98% of Americans have ever heard of! This is going to be a fascinating B-school case study in a year or two. It's one thing for Apple to convince people to pay a huge premium for its design, another entirely to convince people to pay twice as much for a noninteractive energy-storage device that sits in a basement or closet. I'm in awe. Luxury product indeed.
This is more than can be said for the "half price" lead-acid batteries, which need to be periodically checked for corrosion and cleaned. Non-sealed batteries need to be topped off with distilled water annually. All PbA batteries (flooded and AGM!) require the hydrogen vent be checked for obstructions and maintained. That vent is an extra wall penetration for mice, insects, heat loss, etc. The entire battery bank also needs to be equalized every ~6 months, which may or may not be done automatically.
Sounds like the Powerwall's "no interaction" model is already better than the competition.
http://rimstar.org/renewnrg/off_grid_solar_battery_maintenan...
You can save even more money by using FLA if you're willing to do the maintenance. If you're not, the direct comparison is with VRLA. VRLA is much cheaper than the Powerwall on an apples-to-apples basis.
It's hard to point to a specific source describing maintenance procedures that don't exist. For example, a common manufacturer's manual may be found at http://rollsbattery.com/public/docs/user_manual/Rolls_Batter.... Note the difference between FLA and AGM (VRLA) maintenance procedures. Specifically, there are none for the latter.
There are many many people who spend money right now on generators as emergency power sources.
My parents are a great example of a perfect use case for this product. They live in the country, and have 5-6 significant power outages a year, usually in winter. They need a way to automatically deliver power to critical house systems: furnace, well pump, fridge, freezer. Right now they use a large portable generator, but that requires maintenance and a manual engagement. You also cannot leave it unattended for long periods of time. That basically ties them to their house in the winter months, making vacations difficult.
Lots of other markets for this type of thing too. If you have a horse or hobby farm, one of these things keeps the heat on in the barn when the power goes out.
It's a little different with batteries because they don't improve at the same rate tech products do, but they still improve and I think once Tesla gets a couple of those Gigafactories going the batteries will become more appealing to a wider range of customers.
It's also the same with electric cars - 95% of the people still don't want one, even if they had the money for it, because they don't want the range anxiety. Also aren't solar panels still more expensive than buying coal-produced electricity? Or it least it was in the past few years, yet people still installed solar panels.
The bottom line is Tesla only needs some "early adopter" customers to hold it over until the product is cheap/good enough for the mainstream market. And by the looks of it, whether it's in electric cars, solar panels or batteries, that seems to have worked pretty well.
How many people out there want to be an early adopter of a Lennox Air Conditioning unit? Or of a New, more efficient furnace? Or more efficient windows?
The fact remains: the Tesla Powerwall is a "home appliance". The process for buying a new home appliance is the same as any other. You run the calculations, you determine if the appliance saves you money in the long term, and if it does... you go for it.
Moreover, any modern invention could be dismissed as toy/limited use for rich. E.g. Computers, mobile phones, cars... Next generation should be even more competitive.
Flywheel Disel Engines for example will automatically turn on when the power goes out... using a Flywheel to regulate the power the moment energy goes out... while simultaneously being the automatic-startup mechanism for the generator.
It's not like a flywheel + generator is very expensive. There's still a lot of innovation possible in the generator space.
Natural gas generators could be a good option, but only in areas that have natural gas lines already which rules out a lot of rural areas where generators are probably going to be more important anyway.
Of course, the week+ outage is usually due to ungodly amounts of snow... sooooo solar may not be your friend then...
I don't think the Tesla batteries are a good way to lower your home energy costs, but I don't think I would factor in net metering as a reason why, at least not looking 5-10 years out.
This article makes a big point that in the residential/solar panel market the battery is marginal at the moment in most of the US where grid electricity is cheap. Ok, but so what?
1. No kids would be born. They do not make financial sense at all.
2. We all would be living in some nasty environment. Caring for the environment doesn't make much sense for companies.
3. Caring weak, vulnerable people doesn't make any financial sense at all.
that seems like it can't possibly be true.